Packing heavy rains and winds up to 125 miles per hour, a monster typhoon called a “once-in-a-decade event” by the Japan Meteorological Agency is on track to pummel the Tokyo area, home to the crippled Fukushima No. 1 nuclear plant.

“It is the strongest typhoon in 10 years to pass the Kanto region (Tokyo and its vicinity),” Hiroyuki Uchida, the weather agency’s chief forecaster, told a news conference.

“It is expected to have a great impact on the traffic systems in the metropolitan area during commuting hours,” he said.

The storm is causing atomic concerns since the plant has seen a rash of radioactive water spills in recent months, trying to keep its melted reactor cores cool.

The Wall Street Journal says many are “worried about what will happen to the plant and the thousands of tons of radioactive water stored in tanks there.”

“We are making preparations for proper management of contaminated water,” said a spokesman for Tokyo Electric Power Co. “We will patrol places that could have inflows of water (from the storm).”

He indicated cables and hoses have been bundled together, while ground and offshore works have been stopped, as the brunt of the storm hits on Wednesday.

According to Agence France-Presse, the power company announced 114 gallons of polluted water had spilled from a tank as workers tried to remove rainwater dumped at the plant by recent typhoons.

“It has admitted contaminated water may well have flowed into the sea,” AFP reported. “Japan’s atomic watchdog summoned the president of TEPCO for a public dressing-down for sloppy standards at the plant after the incident. The nuclear plant was badly damaged by the tsunami that hit in March 2011. Critics say it remains in a fragile state and at the mercy of extreme weather or other natural hazards.”

The Journal noted, “With a monster typhoon bearing down, are water leaks the real concern?”

Shunichi Tanaka, head of Japan’s Nuclear Regulation Authority, has said for months the leaks are not as serious as many think.

Of greater concern is another major natural disaster, such as an earthquake or powerful winds hitting Fukushima. That could destroy the makeshift tanks and the water processing equipment, releasing radioactive materials into the environment at “much, much greater levels than we are talking about regarding the leaks,” Tanaka warned. “Before that happens, we must clean the water to lower the contamination levels as soon as possible.”